Furnace regulator



Aug. 20, 1940. c. A. HARPMAN FURNACE REGULATOR Filed March 16, 1939 (Zak/es A ar m qr? INVENTOR ATTORNEY Patented Aug. 20,1940 I FURNACE REGULATOR I Charles A. Harpman, Youngstown, Ohio Application March 16, 1939, SerialNo. 262,137 I I 4 Claims. (01. 236-10) This invention relates to a furnace regulator. close the {check thereof at a much faster rate The principal object of this invention is the than would ordinarily be the case. provision of a thermostatic control for a warm With the foregoing and other objects in view air, furnace that is simple in construction, efllwhich will appear as the description proceeds,

' 'ci'ent'in'operation; andcapable of easy installathe invention resides in the combination and "5 tion, arrangement of parts and in the details of con- A further object of thi invention is th prostruction hereinafter described and claimed, it vision of atherm ostatic control for a warm air being. understood that changes in the precise furnace formed of a plurality of stamped parts, d ment of t e i vention herein disclos thus making it inexpensive, to manufacture, can be made within the scope of what is claimed, 10 A further object of this invention is the pro- Ou dep from t e p i Of e i venvision of a thermostatic control for a warm air On- I 5 furnace that is provided with spring t si The invention is illustrated in the accompanymeans for holding the various movable parts in ing aw ng, whe e n: n v

operating positionso that any slack in the jointed Figure is a Side elevation of the device with 16 parts'will'be taken u parts broken away.- Dotted lines on Figure 1 A still further object of this invention is the h w n h r l ive position of h var s p r provision of a thermostatic control for warm air thereof whe the sa e have been actuated.

' UNITED STATES PATENT OFFICE furnaces incorporating the use of a novel lever- Figure 2 is 911109 Plan View of a po ti of age principle whereby the control arm of the e 1 taken on lines 22'thereo-f. device is'actuated with increasing quickness as u e 3 i a enla detail V w partly in it approaches either end of it range of opera,- cross section of one of the actuating arm mounttion, so that when the temperature of the furing brackete Shown in ure nace remains at or near a constant level, the By refelllng t0 the drawing and ure 1 in control arm'of the thermostatic control will move Particular it W l e' e a t e urnace regu- =25 but slightly and when the furnace heats or cools lator p es a base plate i which is in turn rapidly thenovel leverage principle provided bolted to a channel bracket 2. This channel serves to rapidly increase the motion of the conbracket 2 isshown attached to a furnace Casing trol thus in effect opening or closing the draft y means of metal Screws 4 50 th a b -metalmuch faster than'would ordinarily be the case. liC e p on unit Comprising a p tube 5 30 The furnace regulato shown d d s ib d and a steel rod 6 of the regulator are positioned herein has been designed to overcome one of the Slightly above the e of h furnace. The major objections to this general type of thermocopper tube 5 is threaded a s i er end into a static "control apparatus, wherein a bi-metallic threaded p g in the base p ate The steel 5 expanding an'd contracting motion is utilized to T0615 being positioned Within the ppe tube 5 control the draft and chains'of a warm air furand p vi d'w t a pointed inner end, While its In t furnacgyegulgtors of t type outer end is affixed to the outer endof the copheretof ore known to the art many and arious per tube 5 (IlOt'ShOWIl). It Will thus be obvious principles of leverage have been employed with, vvthat any expansion of the ppe tu e 5 Wil be '40 however, the uniform result that the movement Substantially greater than that Of the Steel fl i o Qf the dr ft a check.a,ctuating m of'the 6 and result in a horizontal movement of the regulator'is always in direct relation and. degree Pointed inner end of steel rod The to the expansion and contraction of th b mainder of the regulator utilizes this movement metallic unit incorporated as a part'of th reguas a means of controlling the draft and checks lator. It is, therefore, the purpose of this in- 0f Warm furnace- 7 -4 vention to provide means'in a bi-metallic expanhe u c regulator h W a d described sion and contraction actuated regulator that will herein has been adapted for installation on a speed up the normal motion of such a device, thus warm air furnace adjacent to' the smoke pipe when the furnace cools the device shown and thereof so that the control arm of the regulator '50 described herein "will respond with the normal is positioned directly above the check on the said *or average movement degree but will, upon reachsmoke pipe and connected directly thereto by a ing a pre-determined point of normal movesuitable chain; another chain being connected to ment, be actuated thru the novel leverage printhe control arm and led over one or more pulleys ciples employed therein to rapidly move and thus to the draft door of the furnace. Positioned on &:1eflectivelyopen :thew'draftrof thevfurnace and the base plate I a slotted supporting bracket 1 serves to support a. bar 8 by means of a pin 9 passed therethru; the supporting bracket 1' being positioned slightly above the pointed inner end of the steel rod 5 and the bar 8 positioned adjacent to this pointed inner end of the said steel rod 6. A slot ID in the lower portion of the bar 8 is adapted to engage a pin ll positioned between the upright ends of a pair of L-shaped control arms !2. These control arms I2 being pivoted to a pivot bracket l3 which is in turn attached in any suitable manner to; the base plate l. Positioned between the horizontal portions of the said L-shaped control arms I2, there is a control arm [4 which is pivoted to the said L- shaped control arms l2 by means of a pivot pin 15. In order that this control arm l4 will norfally tend to remain in horizontal'position, as shown in solid lines in Figure 1 a pair ofsprings l6 are provided which lead from an opening II in the inner most end of the control'arm' l' to ,arms N3 of a bracket .19 positioned. -between the said pair of L-shapedcontr'lol arms l2.- j.

In order that the action of th control arm [4 be accelerated when the same moves inresponse to the movement of the-steel rod'fi, a pair 0f lever arms 2!] are provided which are ,pivoted to and spring tensioned by means of spring incor- .porating brackets 2| (see Figure 3) adjustably positioned on the base plate l. 'Theouter ends of these lever arms ware provided-with shoes 22 which are pivoted thereto and are adapted'toslidably engage the inner end of the control arm it. By referring to Figure 1 it will be seen'that the control arm I4 is provided with-3a pair of lugs 23 near the pivot pin, I5,- which 'g'Wlll, when the control arm I4 moves, serve to=j=-limit the sliding action of the lever armslll onthe control arm it. When this occurs the. lever arm 20 'reachingthe lug Z3 serves: to force the control arm M into the position indicatedby, dotted lines in Figure 1. 1

It is obvious that the action shown .in-Figure 1 is that taking place when the furnace-cools and the pointed inner end of the steel rod-B moves inwardly against the bar 8 which 1-111131111'1 moves the control arm l4 thru the pairof L-shaped control arms i 2; it being understood that there- ,verse action takes place when the furnace heats and the control arm M moves upwardly. It will also be seen that there is available axfew degrees of normal movement of the control arm :l4 during which time the shoes"22 on the lever arms -20 slide upon the inner end of the controlarm l4; it being only at such time as one. of the. shoes 20 reaches the lug 23 that the lever .action takes place and thus accelerates the motionlof the control arm Hi. In a practical installation-of this regulator an eyelet 24 at the'extreme-outer end of the control arm is is preferably connected 60' directly by means of a chain to the checkon the smoke pipe of the furnace although'it: is obvious i that if it is desirable to locate the regulator at 'the front of the furnace, the'mo-tion 'of the'control arm may be applied to the draft door of the furnace by passing a connection chain from the eyelet 24 over a pulley so as to reverse the motion of the control arm in relation to'the draft door.

In order that the regulatorbewadjustable; to match, varying heating conditions, azthreaded rod 25 is passed thru a threadedopening in the supporting bracket! and-has its inner endy26 I positioned directly'against the bar 8. Theyouter "end of this threadedrod 25 extendsvoutwardly thru a suitable housing 21andhas.a1=suitable control wheel 2flgincorporatingl a markenvZQsriO- sitioned thereon. A relatively stiff coil spring 30 is positioned between the base plate I and the extreme upper end of the bar 8 and serves to overcome looseness in the pivot joints of the device and to maintain the various portions thereof in operating contact with one another and the actuating steel rod 6.

What I claim is:

1. A thermostatic control for warm air furnaces comprising a base plate adapted for mount said base plate, a pair of L-shaped control arms pivoted to thesaid base plate andadapted to function with the said bar, a control arm piV-r oted between the outer ends ofthe'said pair o f L-shaped control arms, a pair of lugs formed on said control arms, a pair of lever arms adjustably pivoted to the said base plate their outerends adapted to slidably engage an inner end of the said control arm and thereby limited in their Sliding action by said lugs so thatthe'rnovement ofthe L-shaped control arms will result in a leverage action against thesaid control armlwhen the said lever arms reach the said lugs. i

2. A thermostatic control for warm-air fur.- naces comprising .a bi-metallic expansion unit and means for effectively utilizing and -.control,-

lingthe motion caused thereby, said means com- .prising a base. plate to which the said expansion ,unitis attached, a slotted supporting bracket positioned. on the said base plate and adapted to carry a bar on a pin passed therethru, a spring positioned between an upper end of said barand said. base plate, a pair of L-shaped control arms ,pivoted toa bracket positioned onthe said .base plate,'the,upturned ends'of the said L-shaped ,control arms provided with a pin adaptedto rengage a slot in the said bar, a control arm pivoted to the outermost ends of thesaid L-shaped control arms so that the majority of its length extends beyond the outermost ends of the said. control arms and its innermost end is;normally positioned between the said pairof I -shaped control arms 'by' spring tension means, a pair. of lugs formedon said control arm, lever arms adjustably pivoted to the said'base plate and pro-- -vided with shoes adapted to slidably engage the inner end of the said control arm, and thereby limited in their sliding action by the said lugs in such manner as to effectively "apply leverage to the said control arm at such times 'as the said pair of L-shaped control arms are -moved, the said leverage serving to effectively move the said control arm in relation to-the saidpair of .L- shaped control arms.

3. A thermostatic control ling the motion caused'thereby, said meanscomprising a base plate to which the said expansion unit is attached, a slotted supporting bracket:

positioned between an upper end of said bar and said base plate, a threaded'opening in the said for warmair ,fur-, .naces comprising a bi-metallic expansionzunit and means for effectively utilizing and control- :slotted bracket thru whichia .threaded rodvis lfi passed so that it bears against the said bar, a control wheel aflixed to the said threaded rod so that the same may be rotated and will efiectively move the said bar inrelation to the said expansion unit, a pair of L-shaped control arms pivoted to a bracket positioned on the said base plate, the upturned ends of the said L-shaped control arms provided with a pin adapted to engage a slot in the said bar, a control arm pivoted to the outermost ends of the said L-shaped control arms so that the majority of its length extends beyond the outermost ends of the said control arms and its innermost end is normally positioned between the said pair of control arms by spring tension means, a pair of lugs formed on the said control arm, lever arms adjustably pivoted to the said base plate and provided with shoes adapted to slidably engage the inner end of the said control arm in such manner as to effectively apply leverage of one of the lever arms thereto when the lever arm engages one of the said lugs at such times as the said pair of L- shaped control arms are moved the said leverage serving to efiectively move the said control arm in relation to the said pair of L-shaped control arms after the said L-shaped arms and control arm have moved together in their limited rangeand one of the lever arms has reached one of the lugs on the control arm.

4. A thermostatic control for warm air furnaces comprising a channel section attached to the said furnace, a base plate bolted to the said channel section and carrying an expansion unit adapted to extend within the furnace casing and over the dome of the furnace, the said expansion unit comprising a copper pipe threaded into the said base plate and a steel rod attached to the have its inner end engage the said bar adjacent to the said pin, a coil spring positioned between the upper end of the said bar and the said base plate to eifectively hold the said bar in contact with the said steel rod, a pivot bracket'attached to the said base plate, a pair of L-shaped arms pivoted therein, the upturned ends of the said L-shaped arms carrying a pin adapted to engage a slot in the said bar, a control arm pivoted be tween the outermost ends of the said L-shaped arms sothat the majority of its length extends beyond the said ends of the L-shaped arms, a pair of lugs formed on the said control arm, a

pair of lever arms adjustably pivoted to the said base plate having shoes formed on their outer ends adapted to slidably engage an inner end of the said control arm, and thereby limited in their sliding action by the said lugs in such manner that movement of the said L-shap'ed arms will result inone of the said shoes engaging one of the said-lugs and by leverage move the said control arm in relation to the L-shaped arms, spring tension means connecting the innermost end of the said control arm with a bracket positionedbetween the said L-shaped arms so as to tend to -maintain the control arm in horizontal relation with the said L-shaped arms.

CHARLES A. I-IARPMAN. 

